ABSTRACT:
Anhydrous microemulsion have attracted a great deal of attention not only because of their importance in industrial application but also their intrinsic interest. They optimize the performance of a wide spectrum of products and processes. Anhydrous microemulsions are suitable for poorly aqueous soluble drugs and thermodynamically stable multicomponent fluids composed of polar solvent, oil and mixture of a. Liquid administration of drugs is one of the convient and often-advantageous delivery, especially when dealing with children or the elderly for whom pill swallowing can be difficult or even hazardous. Unfortunately many drugs are not soluble in water, while water solution of it may have an unpleasant taste. Some drugs are either unstable in the presence of water or are insoluble in water and therefore cannot be incorporated into aqueous formulations. To overcome these various problems a water free liquid preparation of a number of drugs would be desirable. Two basics strategies could be considered when searching for stable non-aqueous emulsions. One is to design surfactants having two incompatible blocks, each of which is selectively soluble in either of the immiscible liquids. The other approach is to search for a suitable oil immiscible polar liquid that can substantially replace water using emulsifiers. Characterization of non aqueous or anhydrous or oil- in- oil microemulsions shows uniform size distribution of vesicles with micron range. Release profile shows sustained action for extend period of time.